The laser-induced transient absorption spectra of partially reduced or oxidized synthetic porphyrin dimers will be examined. The kinetic data are to be interpreted in terms of a multiphonon relaxation theory. Knowledge of the orientation, distance, and excess electronic energy dependence of the rate will assess the importance of configurational modes in electron transfer rates. Construction of a nanosecond spectrometer is proposed. Axial ligand-metal modes will be enhanced in the resonance Raman spectrum should the exciting radiation be coincident with the pertinent charge-transfer transition; a pulse Raman spectrometer has been constructed for this purpose as well as for examination of pre-resonance Raman spectra of amino acids covalently linked to heme. The approximate SCF-X alpha theory developed in this lab will yield an accurate framework in which the results of magnetic and optical measurements on transition metal complexes can be interpreted. Additionally, it provides a method for understanding dioxygen activation mechanisms in heme-containing oxidases.